let buf_1 = Buffer.alloc(10)
console.log('buf_1', buf_1)

let buf_2 = Buffer.allocUnsafe(8)
console.log('buf_2', buf_2)

let buf_3 = Buffer.from('xin')
console.log('buf_3', buf_3)

let buf_4 = Buffer.from([108, 105, 117])
console.log('buf_4', buf_4)

console.log('转换为字符串', buf_4.toString())

buf_4[0] = 110
console.log('修改', buf_4.toString())